How bad is gun crime in the US? The latest data from the FBI's uniform crime reports provides a fascinating picture of the use of firearms in crimes across America.

Barack Obama is under pressure to tighten gun laws after following the disclosure by police that the Newtown gunman used a semi-automatic assault rifle equipped with "numerous" high-capacity magazines holding hundreds of bullets to carry out his massacre of young children.

And the murder figures themselves are astounding for Brits used to around 550 murders per year. In 2011 - the latest year for which detailed statistics are available - there were 12,664 murders in the US. Of those, 8,583 were caused by firearms.

The FBI crime statistics are based on reports to FBI bureau and local law enforcement. The figures are not complete - there are no stats for Florida or Alabama on firearm murders. But even so it provides a detailed picture of attacks by state.

In fact, gun crime, like all crime across the US (and the UK, for that matter), is going down - you can see how much in the graph above. And the vast majority invlove firearms.

The figures show that California had the highest number of gun murders last year - 1,790, which is 68% of all murders that year and equivalent to 3.25 per 100,000 people in the state. Big as that figure is, it's still down by 3% on the previous year. Other key findings include:

• While gun crime is down in the vast majority of states, it is up in Indiana, Arkansas, North Carolina, Louisiana and several of the smaller states• If you look at the firearms murder rate per 100,000 people, District of Columbia comes out top - with 12 firearms murders per 100,000 men, women and children in the state. There were 77 firearms murders in DC in 2010, down 22% on 2009• DC is followed by Louisiana (10.16) and Mississippi (7.46)• DC is also top for firearms robberies per 100,000 people - with 242.56• If you look at aggravated assaults involving a firearm, Tennessee (137.58) and South Carolina (127.88) come above Arkansas (100.56)

Accused of killing two white girls in South Carolina, George Stinney Jr was tried and electrocuted in just 83 days. As a judge ponders whether to quash the verdict, Karen McVeigh speaks to the families involved